Engine system cooling control



Maly 22, 1945. G. H, G|| L v ENGINE lSYSTEM COOLING CONTROL 'Filed Sept. 16, 1491-12 :Snncntor:

2 or otherfmea'ns vcausing a now of air through the air duct II. -'-Hereafter the liquid cooling agent will be referred to simply as the agent or cooling agent.

As customary in oil cooler practice, lubricating v oil enters the oil cooler I2 from a hot oil delivery piping Il leading from the engine, through an inlet chamber I6 of a Vcooler protective and control iltting I and through an inlet chamber I8 inthe cooler. Oil leaves the cooler through the liquid cooling jacket.

cooler outlet chamber I8 and the outlet chamber 28 of the fitting I5 to enter the cooled oil return piping 2|.

Thev numeral 22 represents schematically la thermostatic control having a conventional thermo-sensitive switch arm 6I therein adapted, up'on a reduction of oil temperature below normal, to engage a contact62 so as to establish, through the conductor 25 and the coll 28b of the reversible motor 28, a circuit which is adapted to operate the motor 28 in a direction to close the flap 3'8.

The connections `between the motor 28 and the flap 38 include a sleeve 29 in threaded engagement with a threaded rod 29awhich is pivoted to an arm 29h attached to the nap k38. The motor 28 may be energized by any suitable source of current which is indicated, for illustrative purposes, as a battery 83. l above normal, the switch arm 6I is adapted to enl gage a. contact to establish, through a conductor 21 and the coil 28a of the motor 28, a circuit for operating the motor in a direction to open the flap 38. l

To ensure closing of the flap 38 when the cooler I2 is filled with cold viscous oil and especially to l care for the congealing of oil upon the air tubes of' the cooler I2, a control device 23 within the iltting I5 which is responsive to the pressure drop between the inlet chamber I8 and outlet chamber 20, to establish a ycircuit through the conduc-` tor 21 and the coil 28h of the motor 28 to override the action of the thermostatic control device Upon a rise in oil temperature emessa is withdrawn through a come@ emgwthfr Supplied @0x-m engine Y drawal piping 31 and The fitting I3' is formed with inlet chambers 38 and 4I separated by a partition wall 5I `oi? the fitting in which 1S formentV port opening-enr valve seat 48. 'I'he inlet-,chamber 4I communicates with the inlet chamber 340i the agent cooler by means of an opening 33m-the walls of the n" iv. i.

.chamber 39 which receives theV cooling'agent from the 'cooler through an opening port 36 registering with Ithe cooler outlet chamber and which discharges the cooling agent into the cooledv 4 liquid withdrawal piping 31.

A valve stem 42, upon whichV are mounted oppositely facing valve elements l! and l5, is guided in its longitudinal movement; by a socket 43 formed in an, interior lug on one of the walls of the fitting I3.v Valve element M inthe inlet chamber 38 engages valve seat 48. Valve element 45 also in the inlet chamber 38 engages a valve seat 48 formed in a port opening in the partition wall 5.2 of the fitting i3' which separates the inlet chamber 38 from the outlet chamber 39.

and at the low air'listream speedswithin the duct y l which exists when the shuttersare in extreme sure drop control'to .thaw out congealed oil in 22 and'operate the motor 28 to close the shutter 38 irrespective of the temperature of the oil leaving the cooler or oi' theresponse of the thermostatic control device 22 to that temperature. The device 23l has a piston or diaphragm 55 disposed in an opening in the partition wall between the inlet chamber IB and the outlet chamber 20, and aspring 51 which resists rightward movement of the member 5 5. When oil thickens within the cooler I2, the increase in pressure differential between the chambers I6 and 28 will cause l the member 55 to move rightward against the action of the spring 51, thereby actuating the pressure-override device 23.

The connection to the motor 28 may be carried through a conventional junction box, indicated schematically in broken lines at 25. static electric control systems embodying a pressure override and a shutter operating, reversible motor powered screw jack, are known in the art,

as shown, for example, by the patent to Hannon, No. 2,314,937, issued March 30, 1943, on an ap plication illed February 14. 1942. l An agent cooler I3 of the type well known to the radiator art. similarly provided with air tubes through which air flow of the duct I I is passed. receives the cooling agent, from the hot cooling agent deliveryf piping 32 leading from theengine. through a control tting I3 from which the cooling agent passes to an-inlet chamber 3l of the .agent cooler tothe cooler core. The cooling agent from the agent" cooler core passes through a cooler outlet chamber 35 .into the control tting I3' from which it Thermoables.

The end of valve stern l2 which lies in outlet chamber 39 has secured to it the live end of `a thermostat l1, the dead end 43 of which is mount,-

ed in a supporting wall 58 carried by the fitf-f.A c

ting-I3.

The area of themair tubes. of the agent cooler I3 is of suillcient extent to provide the cooler with a capacity to coolA to normal -temperature the 'maximum liquid stream iiow from the engine cooling jacket at maximum atmospheric temperatures closedposition. As a. result oithis feature of design of the agent cooler, when the flap 38 is ventirely closed by the action of the yoil cooler pres-v` ing at it from a somewhat different standpoint,

the heat exchange walls ofthe liquid cooler must be yso designed as to heat transference-capacity that when the air iiap is in open position the liquid cooler will cool to normal temperature under maximum atmospheric temperature conditions and at minimum aircraft speed relative to the atmosphere, a stream greatly in excess of the stream of liquid coming from the enginejacket at maximum engine speed.

From the foregoing description.: the performance characteristics of the dual cooling system y are apparent. Under ordinary operative condivtions, thel thermostatic'regulator 22 maintains the temperature of the oil leaving the oil cooler I2 at proper temperature for returnto the engine .in a. satisfactory manner. vThis vtemperature regulation accomplishes adjustment of the ap 38 in correspondence withthe oil and air vari- Adjustment of the position of the flap 38 by the thermostatic regulator 22 also maintains the temperature of the cooling agent leaving the agent cooler at a temperature .which is roughly the paper temperahirefcrrehirntotheemdne cooling jacket. The thermostatieally controlled 'valves u and Ilgive further rennement to the rising to an'excessive value by reason of the over- Y lsized heat transfer surfaces of the agent cooler i I, through which all or most of the cooling agent may thenbepassedasaresultoftheclosingof the valve II and opening of the valve ll by the thermostat l1 under those conditions.

I claim as my invention:

`l. In -a liquid cooling system for an internal combustion engine having an oil circulating system and a cooling agent circulating system, the combination of an oil cooler connected between the hot lubricating oil delivery piping and the cooled oil return piping of the oil circulating systemV of the engine; a liquid cooler connected between the hot cooling jacket liquid delivery piping and the cooled liquid return piping oi the cooling agent circulating system of the engine;

, a common air stream means providing an air stream in heat exchange relation with both of said coolers;A means regulating the iiow rate of said air stream; a-control means for said regulating means responsive to the temperature o! the oil in said oil circulating system acting to increase the air ilow rate in response to super-normal oil temperatures and to decrease the air how rate in response to subnormal oil temperatures; a bypass passage means' between the inlet and outlet of said liquid cooler; a valve for opening'and closing said bypass passage; and a thermostat re- .sponsive to the temperature of the liquid treated by said liquid cooler for the operation of said valve acting to close said valve in response to super-normal liquid temperatures and to open said valve in response to subnormal liquid temperatures.

2. In a liquid cooling system for an internal combustion engine having an oil circulating system and a cooling agent circulating system, the

combination of: an oil cooler connected between a the hot lubricating oil delivery piping and tle cooled oil return piping of the cooling agent circulating system of the engine; a liquid cooler connected between the hot cooling jacket liq'uid delivery piping and the cooled liquid return piping of the cooling agent circulating system of the engine; a common air stream means providing an air stream in heat exchange relation with both. of said coolers; means regulating the flow rate ofsaid air stream; a control means for said regulating means responsive to the temperature of the oil leaving said oil cooler acting to increase the air now rate in response to super-normal oil temperatures and to decrease the air flow rate in response to subnormal oil temperatures; a bypass passage means between the inlet and outlet ofv said liquid cooler; a valve for opening and closing said bypass passage; and. a thermostat responsive to the temperature of the liquid leaving said liquid cooler for the operation of said valve acting to close said valve in response to supernormal liquid temperatures and to Open said valve in response to subnormal liquid temperatures.

3. In a liquid cooling system for an internal .cooledoilreturnpipingo the .hot lubricating oil said coolers; means regulatingthe iiow rate ofsaid air stream; a control means for said regulating means responsive to the temperature of the oil leaving said oil cooler acting to increase the air iiow rate in response to super-normaloil temperatures and to decrease the airflow rate in response to subnormal oil tempratures; a supplementary control means for said regulating means effective in overriding relation to said iirst mentioned control means and in'response to an excessive pressure drop between the inlet and outlet of said oil cooler to operate said regulating means to decrease the iiow rate of said sir stream: a bypass let of said liquid cooler; a valve for opening and closing said bypass passage; anda thermostat responsive to the temperature of the liquid leaving said liquid cooler for the operation of said super-normal liquid temperatures vand to open said valve in response to subnormal liquid temf 5. The combination dennen in claim 2 in which f the heat exchange walls of said liquid cooler are 4 so related as to area and to capacity of heat transference that said liquid cooler will cool to normal `temperature at maximum atmospheric temperatures and at minimum aircraft speeds relative to the atmosphere, a stream in excess of the stream of liquid coming from the engine jacket, at maximum engine speed.

6. In a cooling system for an internal combustion engine having an oil circulating system and a cooling agent circulating system, the combination of: a duct through which a flow of cooling air may pass;A an oil cooler disposed in said duct so' that air may pass therethrough, said cooler being connected in said oil circulating system so as to cool hot oil therein: means for controlling the flow of air through said duct in accordance with the temperature of the oil which passes through said cooler whereby the temperature of the oil leaving the cooler may beV regulated; a cooling agent radiator disposed in said ductvso that air may pass therethrough, said radiator being connected in said cooling agent circulating system so as to cool heated cooling Aagent therein, said radiator being of excess capacity so as t0 cool said agent to a subnormal temperature; and

bypass means connecting the inlet and the outlet passage means between the inlet and outcooling agent circulating system a stream of agent of substantially normal temperature.

7. In a cooling system for an internal combustion engine having an oil circulating system and a cooling agent circulating system, the combination of: a duct through which a flow of cooling air may pass; an oil cooler-disposed in said duct so that air may pass therethrough, said cooler being connected. in said oil circulating system so as to cool hot oil therein; means for controlling the flow of air through said duct in accordance with the temperature oi! the oil which passes through said cooler whereby thel temperature of the oil leaving the cooler may be regulated; a

'cooling agent radiator disposed in said duct so that air may pass therethrough, said radiator -being connected in said cooling agent circulating system so as to cool heated cooling agent therein. I

said radiator being ,of excess capacity so as t0 cool said agent to a subnormal temperature; and bypass means connected so as to bypass part of the heated agent around at least a portion of said radiator, said bypass means having a, thermostat valve for proportioning 'the ow oi' said agent through said radiator and through said retest No. 2.575685.

l .It is hereby certi ofthe-above fannb'ered patent column, I1ine52',"

l instead f-o11 correction therein that theV the .Patent Office.

GEoRcE Bassani" GILL,

and tluough said bypass so as to produce in said bypass so as to produce in said cooling agent circulating system a stream of agent of substantially normal temperature. f

8. In a cooling system for an internal combustion engine having an oil circulating system and .a cooling agent circulating system, the combination of: a duct through which a flow of cooling system so as to cool heated cooling agent therein,

said radiator being of excess capacity so as to cool said agent to a. subnormal temperature; and thermostatic means for controlling the ow of agent through said radiator, soasto produce in said cooling agent circulating system a stream of agent of substantially-normal temperature.

' GEORGE HERBERT GILL.

CERTIFICATE OF CORRECTION.

Mey azi-'1915.

riad that error anpea'rs in the printed specification v:requiring correction as follows: Page '5, first claim strike out: the wordsv "cooling agent and that thesaid Letters Patent should be read with this same m'ayconformto the recordfof the case in and/ insert sighed hastened this 1 1thany or september, A. D. 19h15'.I

LeslieFraze'r First AssistantA Commissioner of Patents.

cooling agent circulating system a stream of agent of substantially normal temperature.

7. In a cooling system for an internal combustion engine having an oil circulating system and a cooling agent circulating system, the combination of: a duct through which a flow of cooling air may pass; an oil cooler-disposed in said duct so that air may pass therethrough, said cooler being connected. in said oil circulating system so as to cool hot oil therein; means for controlling the flow of air through said duct in accordance with the temperature oi! the oil which passes through said cooler whereby thel temperature of the oil leaving the cooler may be regulated; a

'cooling agent radiator disposed in said duct so that air may pass therethrough, said radiator -being connected in said cooling agent circulating system so as to cool heated cooling agent therein. I

said radiator being ,of excess capacity so as t0 cool said agent to a subnormal temperature; and bypass means connected so as to bypass part of the heated agent around at least a portion of said radiator, said bypass means having a, thermostat valve for proportioning 'the ow oi' said agent through said radiator and through said retest No. 2.575685.

l .It is hereby certi ofthe-above fannb'ered patent column, I1ine52',"

l instead f-o11 correction therein that theV the .Patent Office.

GEoRcE Bassani" GILL,

and tluough said bypass so as to produce in said bypass so as to produce in said cooling agent circulating system a stream of agent of substantially normal temperature. f

8. In a cooling system for an internal combustion engine having an oil circulating system and .a cooling agent circulating system, the combination of: a duct through which a flow of cooling system so as to cool heated cooling agent therein,

said radiator being of excess capacity so as to cool said agent to a. subnormal temperature; and thermostatic means for controlling the ow of agent through said radiator, soasto produce in said cooling agent circulating system a stream of agent of substantially-normal temperature.

' GEORGE HERBERT GILL.

CERTIFICATE OF CORRECTION.

Mey azi-'1915.

riad that error anpea'rs in the printed specification v:requiring correction as follows: Page '5, first claim strike out: the wordsv "cooling agent and that thesaid Letters Patent should be read with this same m'ayconformto the recordfof the case in and/ insert sighed hastened this 1 1thany or september, A. D. 19h15'.I

LeslieFraze'r First AssistantA Commissioner of Patents. 

